Packing gland for soft-cored underwater electrical cable



Dec. 10, 1963 AN. J. HEIKKINEN` 3,113,999

L PACKING GLAND FOR soFT-coREn UNDERWATER ELECTRICAL CABLE Filed May 24,1962 l Il i 1 V nllgg-kg Mmm Q A\\\\ lZal /32 /NVE/VTOR.

NORMAN J. HEIKKINEN 1 lr u ATTY.

57PM Emmen United States Patent 3,lli3,999 PCKENG @LAND FR SFTLLCREDUNDER- WATER ELECERHCAL @ABLE y Norman LF. Heiklrinen, Washington, DAC.,assigner to the United. States of America as represented by theSecretary ot the Navy Filed'May 2d, i962, Ser. No.. 197,56?? Claims.(Si. '17d-dit) (Granted under Title 35, US. Code (i952), sec. 266) Theinvention described herein may be manufactured and used by or for theGovernment of the United States of America for governmental purposeswithout the payment of any royalties thereon or therefor.

This invention relates to sealing apparatus and more particularly to apacking gland yfor soft core multi-conductor cables subject to highpressures for long durations.

When exposed to very high pressures, Ithe jacket of multi-conductorcables does not maintain its round shape and assumes the shape or" thekinner core or bundle. This fact, as well as the squeeze caused by theexternal pressure on the core, it not desirable in many types of cables.For example, when the core includes coaxial cables and multiple shieldedconductors, insulationl resistance is of paramount` importance. Adso,the use of expensive equipment and the need for safety and/ or preciseresults will not tolerate any leakage or cable core creep when the cableis exposed to high pressures. At the present time, existing packingglands Sutter the disadvantages of allowing cable squeeze and cableextrusion at high pressures, thereby impairing sealing reliability underhigh pressure conditions. p

The general purposeof this invention is to provide a packing gland whichembraces all the `advantages of similarly employed packing glands andpossesses none of the o-f the Kaforo-described disadvantages. To attainthis, the present invention contemplates a unique packing glandconstruction whereby cable squeeze and cable extrusion at high pressureconditions are eliminated by utilizing multiple cable jackets to absorball cable lthrusts and greatly reduce the packing washer squeezetransmitted to the inner bundle or core.

An object of the present invention is the provision of a new andimproved packing gland for soit core multiconductor cables utilized inextreme pressure environments. j

Another object is to provide a packing gland of the character describedwhich eliminates cable squeeze and extrusion in high pressureapplications.

Affurther object of theinvention is the provision ofk a packing glandwhich is small, compact and reliable, requires no maintenance oradjustment under varying pressure conditions, and which may be easilyassembled remote from the area in which it is -to be used.

Still another object is to provide a packing gland for a multi-conductorcable utilizing multiple cable jackets which results in minimized creepand accordioning of the outside jacket, increased absorption of 4thecablek inthe illustrated example of the invention, the reference numerallli designates the housing for the packing gland which has a ilangedportion 12 formed integrally there- Y the bore i3.

ice

2 with and having apertures therein for mounting purposes. rifhe housing1li has a circular bore i3 therein and a central aperture la in the endi5 thereof which extends into Adjacent the open end i6 of the housing,theV bore i3 is provided with a threaded portion i7 to allow for theclosing of the open end le by the insertion of a threaded nut 33. Acircular plate i8 having an integral ramp portion y191 and a centralaperture 2d therethrough of the same size as the aperture ld is disposedwithin the housing bore 13 adjacent the end i5. The plate 1.3 may beformed'of Teflon or a similar material and is in sealing relationshipwith the housing end l5 because of the positioning of an O-ring 2lbetween the plate it and the end i5.

The cable core or bundle 22 extends through the apertures 2d and i4,while the inner cable jacket 23 is retained between the ramp portion l@and a steel sealing block spacerr 24- having a surface 2S parallel tothat of the ramp portion i9. A pair of O-rings 26 are provided betweenthe block 2d and the inner cable jacket 23 to increase the sealingreliability of the gland. The sealing block 2d is provided with anaxially extending sleeve Z7 lformed integrally theiewith which extendsbetween the inner cable jacket 23 and the outer cable jacket 2S for apurpose to be described hereinafter. The sealing block 24 is providedwith `a circular recess 29 adjacent the sleeve 27 to receive the end ofthe outer cable jacket 23.

A plurality of resilient (preferably rubber) washers Sli are disposedadjacent the sealing block spacer 211; and around the outer cable jacket2S and the sleeve 27. A steel washer 32 `is provided adjacent theresilient washers 3i, and a plug 33 having a central aperture 34toreceive the cable is threaded into the open end lo of the housing intocontact with the steel washer 3?.. As the plug 33 is advanced, thewashers 31 are compressed and expanded transversely for better sealing,and the spacer 2dl Vis forced against the ramp portion il? to retain theinner cable jacket 2,3 therebetween. y

The retention of the end of the inner cable jacket 23 between the rampportion i@ and the sealing block spacer surface 2S results in asubstantial reduction in cable extrusion and therefore preventsiaccordioning of the outer cable jacket 2S. in addition, the provisionof the axially extending sleeve 27 between the inner and the outer cablejackets 23 `and 28 respectively insures against transmission of theresilient washer expansion to the inner core or bundle of the cableowing to the rigidity of the sleeve 27. Therefore, because of thesealing reliability of the present invention, such a packing gland maybe very useful in submarine torpedo door umbilical cord installation,mines, complex missile connections, external connections to submarineradar towers, submarine bridge controls, deep ocean experimental craftyand equipment, or other possible trouble leak areas where cable squeezeon multi-conductor cables is not desired or cannot be tolerated.

While the invention has been described in detail with j reference to thepreferred form shown it will be understood that modications may be madewithin the scope of the invention as defined in the appended claims.

What is claimed is:

l. A packing gland for -a soft-cored underwater electrical cable havinginner and outer cable jackets comprising a hollow housing having an openend and a closed end with an aperture therein for receiving the cablecore therethrough, a plate member disposed within said housing adjacentsaid closed end and having `an axially eX- tending ramp portion uponwhich an end portion of the inner cable jacket is disposed and anaperture therethrough to receive the cable core, a sealing block locatedwithin said housing and surrounding said ramp portion and the endportion of the inner cable jacket to retain the inner jacket on saidramp portion, said sealing block having i lllhb Patented Dec. i0, i963`an axially extending sleeve located between the inner and outer cablejackets and a groove therein adjacent said sleeve to receive the endportion of the outer cable jacket surrounding said sleeve, a pluralityof washers disposed within said housing and surrounding said sleeve andthe inner and outer cable jackets, and `a plug insertable in said openend of said housing to seal said open end and apply pressure to saidwashers, said spacing block and said ramp portion, whereby the innercable jacket is retained in position to avoid the extrusion thereof andsaid sleeve prevents the transmission of washer squeeze pressure to theinner jacket and cable core.

2. The apparatus of claim 1 wherein said housing has an external llangeportion formed integrally therewith and a plurali-ty of holes thereinfor mounting purposes.

3. The apparatus of claim 1 wherein O-rings are provided between saidsealing block and the end portion of the inner cable jacket adjacentsaid ramp portion.

4. The apparatus of claim 1 wherein said washers coniprise a pluralityof rubber washers and a steel washer adjacent thereto.

5. The apparatus of claim '1 wherein said plug is threaded and `theinterior surface of said housing adjacent the open end thereof isthreaded to retainably receive said plug therein.

References Cited in the le of this patent UNITED STATES PATENTS2,497,706 Wetherill Feb. 14, 195() 2,655,638 Allen Oct. 13, 19532,785,385' Figueira Mar. 12, 1957 FOREIGN PATENTS 121,738 Germany July2, 1901 528,417 Germany June 29, 1931

1. A PACKING GLAND FOR A SOFT-CORED UNDERWATER ELECTRICAL CABLE HAVINGINNER AND OUTER CABLE JACKETS COMPRISING A HOLLOW HOUSING HAVING AN OPENEND AND A CLOSED END WITH AN APERTURE THEREIN FOR RECEIVING THE CABLECORE THERETHROUGH, A PLATE MEMBER DISPOSED WITHIN SAID HOUSING ADJACENTSAID CLOSED END AND HAVING AN AXIALLY EXTENDING RAMP PORTION UPON WHICHAN END PORTION OF THE INNER CABLE JACKET IS DISPOSED AND AN APERTURETHERETHROUGH TO RECEIVE THE CABLE CORE, A SEALING BLOCK LOCATED WITHINSAID HOUSING AND SURROUNDING SAID RAMP PORTION AND THE END PORTION OFTHE INNER CABLE JACKET TO RETAIN THE INNER JACKET ON SAID RAMP PORTION,SAID SEALING BLOCK HAVING AN AXIALLY EXTENDING SLEEVE LOCATED BETWEENTHE INNER AND OUTER CABLE JACKETS AND A GROOVE THEREIN ADJACENT SAIDSLEEVE TO RECEIVE THE END PORTION OF THE OUTER CABLE JACKET SURROUNDINGSAID SLEEVE, A PLURALITY OF WASHERS DISPOSED WITHIN SAID HOUSING ANDSURROUNDING SAID SLEEVE AND THE INNER AND OUTER CABLE JACKETS, AND APLUG INSERTABLE IN SAID OPEN END OF SAID HOUSING TO SEAL SAID OPEN ENDAND APPLY PRESSURE TO SAID WASHERS, SAID SPACING BLOCK AND SAID RAMPPORTION, WHEREBY THE INNER CABLE JACKET IS RETAINED IN POSITION TO AVOIDTHE EXTRUSION THEREOF AND SAID SLEEVE PREVENTS THE TRANSMISSION OFWASHER SQUEEZE PRESSURE TO THE INNER JACKET AND CABLE CORE.